supply. Included in the package are the switching control-
ler, power FETs, inductor and all support components.
Operating over an input voltage range of 2.375V to 5.5V,
the LTM4604 supports an output voltage range of 0.8V
to 5V, set by a single resistor. This high efficiency design
delivers up to 4A continuous current (5A peak). Only bulk
output capacitors are needed to complete the design.
The low profile package (2.3mm) enables utilization of
unused space on the bottom of PC boards for high density
point of load regulation. High switching frequency and
a current mode architecture enable a very fast transient
response to line and load changes without sacrificing
stability. The device supports output voltage tracking for
supply rail sequencing.
Fault protection features include foldback current protec-
tion, thermal shutdown and a programmable soft-start
function. The LTM4604 is offered in a space saving and
thermally enhanced 15mm
×
9mm
×
2.3mm LGA package
and is Pb free and RoHS compliant.
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
μModule
and UltraFast are trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
Complete Standalone Power Supply
Wide Input Voltage Range: 2.375V to 5.5V
4A DC, 5A Peak Output Current
0.8V to 5V Output
Output Voltage Tracking
±2%
Total DC Error
UltraFast
TM
Transient Response
Power Good Indicator
Current Mode Control
Current Foldback Protection, Parallel/Current Sharing
Up to 95% Efficiency
Programmable Soft-Start
Micropower Shutdown: I
Q
≤ 7μA
Overtemperature Protection
Small and Very Low Profile Package:
15mm × 9mm × 2.3mm LGA
APPLICATIONS
■
■
■
■
■
Telecom and Networking Equipment
Servers
Storage Cards
ATCA Cards
Industrial Equipment
TYPICAL APPLICATION
Efficiency vs Output Current
3.3V to 2.5V/4A μModule Regulator
V
IN
3.3V
10μF
6.3V
V
IN
PGOOD
COMP
GND
V
OUT
FB
V
IN
2.37k
LTM4604
RUN/SS TRACK
V
OUT
2.5V
4A
22μF
6.3V
×2
4604 TA01a
100
95
90
EFFICIENCY (%)
85
80
75
70
65
0
1
2
3
OUTPUT CURRENT (A)
"$" /
V
IN
= 3.3V
V
OUT
= 2.5V
4
4604f
1
LTM4604
ABSOLUTE MAXIMUM RATINGS
(Note 1)
PIN CONFIGURATION
TOP VIEW
TRACK
A
1
2
3
4
5
6
7
8
9
10
11
GND
V
OUT
LGA PACKAGE
66-PIN (15mm
´
9mm
´
2.3mm)
T
JMAX
= 125°C,
θ
JA
= 25°C/W, WEIGHT = 0.86g
SW
RUN/
SS
GND
B
V
IN
COMP
FB
C
D
E
PGOOD
F
G
V
IN
, PGOOD ................................................. –0.3V to 6V
COMP, RUN/SS, FB, TRACK .........................–0.3V to V
IN
SW, V
OUT
........................................–0.3V to (V
IN
+ 0.3V)
Operating Temperature Range (Note 2) ... –40°C to 85°C
Junction Temperature ........................................... 125°C
Storage Temperature Range................... –55°C to 125°C
ORDER INFORMATION
LEAD FREE FINISH
LTM4604EV#PBF
LTM4604IV#PBF
TRAY
LTM4604EV#PBF
LTM4604IV#PBF
PART MARKING*
LTM4604V
LTM4604V
PACKAGE DESCRIPTION
15mm
×
9mm
×
2.3mm LGA
15mm
×
9mm
×
2.3mm LGA
TEMPERATURE RANGE
–40°C to 85°C
–40°C to 85°C
Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.
Consult LTC Marketing for information on non-standard lead based finish parts.
For more information on lead free part marking, go to:
http://www.linear.com/leadfree/
This product is only offered in trays. For more information go to:
http://linear.com/packaging/
ELECTRICAL CHARACTERISTICS
SYMBOL
V
IN(DC)
V
OUT(DC)
The
●
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
IN
= 5V unless otherwise noted. See Figure 15.
PARAMETER
CONDITIONS
Input DC Voltage
Output Voltage, Total Variation C
IN
= 10μF
×
1, C
OUT
= 22μF
×3,
R
FB
= 5.69k 0.5%
with Line and Load
V
IN
= 2.375V to 5.5V, I
OUT
= 0A to 4A, 0°C ≤ T
A
≤ 85°C
V
IN
= 2.375V to 5.5V, I
OUT
= 0A to 4A
I
OUT
= 0A
I
OUT
= 0A, C
IN
= 10μF, C
OUT
= 22μF
×3,
RUN/SS = 0.01μF, V
OUT
= 1.5V
V
IN
= 3.3V
V
IN
= 5V
V
IN
= 3.3V, V
OUT
= 1.5V, No Switching
V
IN
= 3.3V, V
OUT
= 1.5V, Switching Continuous
V
IN
= 5V, V
OUT
= 1.5V, No Switching
V
IN
= 5V, V
OUT
= 1.5V, Switching Continuous
Shutdown, RUN = 0, V
IN
= 5V
●
MIN
2.375
1.478
1.470
1.75
TYP
MAX
5.5
1.522
1.522
2.3
UNITS
V
V
V
V
●
1.5
1.5
2
Input Specifications
Undervoltage Lockout
V
IN(UVLO)
Threshold
Peak Input Inrush Current at
I
INRUSH(VIN)
Start-Up
I
Q(VIN NOLOAD)
Input Supply Bias Current
0.7
0.7
60
28
100
35
7
A
A
μA
mA
μA
mA
μA
4604f
2
LTM4604
ELECTRICAL CHARACTERISTICS
SYMBOL
I
S(VIN)
PARAMETER
Input Supply Current
The
●
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
IN
= 5V unless otherwise noted. See Figure 15.
CONDITIONS
V
IN
= 2.5V, V
OUT
= 1.5V, I
OUT
= 4A
V
IN
= 3.3V, V
OUT
= 1.5V, I
OUT
= 4A
V
IN
= 5V, V
OUT
= 1.5V, I
OUT
= 4A
V
IN
= 3.3V, V
OUT
= 1.5V
MIN
TYP
2.9
2.2
1.45
MAX
UNITS
A
A
A
A
Output Specifications
I
OUT(DC)
Output Continuous Current
Range (See Output Current
Derating Curves for Different
V
IN
, V
OUT
and T
A
)
ΔV
OUT(LINE)
Line Regulation Accuracy
V
OUT
ΔV
OUT(LOAD)
V
OUT
V
OUT(AC)
f
S
ΔV
OUT(START)
Output Ripple Voltage
Load Regulation Accuracy
4
V
OUT
= 1.5V, V
IN
from 2.375V to 5.5V, I
OUT
= 0A
V
OUT
= 1.5V, 0A to 4A
V
IN
= 3.3V
V
IN
= 5V
I
OUT
= 0A, C
OUT
= 22μF/X5R/Ceramic
×3
V
IN
= 3.3V, V
OUT
= 1.5V
V
IN
= 5V, V
OUT
= 1.5V
I
OUT
= 4A, V
IN
= 5V, V
OUT
= 1.5V
C
OUT
= 22μF
×3,
V
OUT
= 1.5V, RUN/SS = 10nF,
I
OUT
= 0A
V
IN
= 3.3V
V
IN
= 5V
C
OUT
= 22μF
×3,
V
OUT
= 1.5V, I
OUT
= 1A Resistive Load,
TRACK = V
IN
and RUN/SS = Float
V
IN
= 3.3V
V
IN
= 5V
Load: 0% to 50% to 0% of Full Load,
C
OUT
= 22μF
×3
Ceramic
V
IN
= 5V, V
OUT
= 1.5V
Load: 0% to 50% to 0% of Full Load
V
IN
= 5V, V
OUT
= 1.5V
C
OUT
= 22μF
×3
V
IN
= 3.3V, V
OUT
= 1.5V
V
IN
= 5V, V
OUT
= 1.5V
I
OUT
= 0A, V
OUT
= 1.5V, 0°C ≤ T
A
≤ 85°C
I
OUT
= 0A, V
OUT
= 1.5V
●
0.1
0.2
%
●
●
0.3
0.3
10
12
1.25
0.6
0.6
%
%
mV
P-P
mV
P-P
MHz
Output Ripple Voltage
Frequency
Turn-On Overshoot
20
20
mV
mV
t
START
Turn-on Time
1.5
1.0
ms
ms
ΔV
OUT(LS)
t
SETTLE
I
OUT(PK)
Control Section
V
FB
I
FB
V
RUN
I
TRACK
V
TRACK(OFFSET)
V
TRACK(RANGE)
R
FBHI
PGOOD
ΔV
PGOOD
R
PGOOD
Peak Deviation for Dynamic
Load Step
Settling Time for Dynamic
Load Step
Output Current Limit
25
10
8
8
0.792
0.788
0.5
0.8
0.8
0.2
0.65
0.2
30
4.99
0.808
0.812
0.8
mV
μs
A
A
V
V
μA
V
μA
mV
V
kΩ
Voltage at FB Pin
●
RUN Pin On/Off Threshold
TRACK Pin Current
Offset Voltage
Tracking Input Range
Resistor Between V
OUT
and
FB Pins
PGOOD Range
PGOOD Resistance
TRACK = 0.4V
0
4.975
0.8
5.025
Open-Drain Pull-Down
±7.5
90
150
%
Ω
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2:
The LTM4604E is guaranteed to meet performance specifications
from 0°C to 85°C. Specifications over the – 40°C to 85°C operating
temperature range are assured by design, characterization and correlation
with statistical process controls. The LTM4604I is guaranteed over the full